A method and an apparatus for detecting a possible leak in a vacuum package 104, in which the vacuum package is received within a wrapping wall 102 at least essentially consisting of a gas- tight, flexible wrapping foil adapted for substantial adjustment to the contours of the vacuum package under the influence of overpressure, so that the vacuum package is tightly enveloped by the wrapping wall. Overpressure is applied to the wrapping foil such that this adjustment to the contours of the vacuum package is effected without sealing any leak present, ensuring that the pressure exteriorly of the vacuum package remains higher than the pressure within said vacuum package. Hermetic sealing from the outside air is effected in the residual space 118 remaining between the vacuum package and the wrapping wall during a predetermined detection period, the pressure being gauged in function of the time.